adults for investment in primary and secondary school education, has led most developing countries to invest a substantial proportion of government revenues in education. Even with the doubling of educational investment, the absolute number of illiterates has actually increased in many developing countries with high population growth rates. It is no accident that countries with high birth rates and low national income are those with much illiteracy. Furthermore, the demand for education is so great in many societies that a substantial portion of educational development is outside of the government sector. In the 19th century, religious institutions in Europe provided much of the money for educational development. In India today, the private sector, especially caste associations, has been creating educational institutions. And in parts of southeast Asia, Chinese voluntary associations have also been building their own schools. However, in spite of these efforts in both the public and private sectors, few developing countries have been able to achieve the goal of universal primary education. The government of a population with an increasing number of school-age children is often under pressure to divert the investment of funds from industry to education in order to achieve universal literacy and universal primary education. Moreover, as long as the number of children in the school-age group continues to grow, educational planners are confronted with a moving target. Substantial increases in governmental expenditure are needed simply to keep the same proportion of children of school age in the schools. In India, for example, the number of children below the age of 15 increased from 138.6 million in 1951 to 180.4 million in 1961, an increase of nearly 42 million or 30 percent.* If universal education is not achieved and only a portion of the school-age group is actually in school—a pattern in most developing societies—it is invariably the children of the poorest groups who are not in school. The early effects of educational development may thus be to improve the opportunities for the children of the urban middle classes, the children of the peasant proprietors, and perhaps for those of the urban working class, while the children of tenant farmers and landless laborers are left behind. Since occupational levels often coincide with differences in religion or caste or tribe or language, a half-developed system of primary and secondary school education may sharpen both class and ethnic differences. There is an impressive amount of evidence that many modern revolutionary movements are associated with an increase in the number of young adults. In a stimulating and original article, Moller has argued that in any society, regardless of social and economic conditions, an increase in the number of youths makes for an increase in social turbulence (32). The reason that *See Gavin W. Jones, "Effect of Population Change on the Attainment of Educational Goals in the Developing Countries," in this volume.